Optical fibers are now commonly used as a telecommunications transmission medium. The optical fibers are packaged in protective cables, and the cables are drawn through underground ducts, ploughed into trenches or strung between poles.
For the assembly of optical fiber telecommunications systems and for maintenance and repair of such systems, optical fibers must be joined end-to-end to provide optical coupling between adjacent lengths of optical fiber. Optical fiber connectors are provided where a need for future disconnection and reconnection is anticipated. Where limited need for future disconnection and reconnection is anticipated, optical fiber splices are provided.
In one conventional method for splicing optical fibers, prepared ends of the optical fibers are brought into abutting alignment and heated by means of an electric arc or flame to cause the ends of the fibers to fuse together. While this splicing method is very effective, some field personnel are reluctant to use an electric arc or flame in underground environments in case explosive gases may be present. Moreover, the equipment which supplies the electric arc or flame is bulkier and more expensive than desired.
In other known methods for splicing optical fibers, the prepared ends of the optical fibers are brought into abutting alignment within a mechanical splice and clamped or cemented within the mechanical splice. For example, U.S. Pat. No. 4,730,892, which was issued Mar. 15, 1988, in the names of John C. Anderson et al, describes a mechanical splice which comprises a base member, an elastomer alignment sleeve and a cover member. The base member has a v-groove which extends along a central portion of the base member. The elastomer alignment sleeve fits into the v-groove. The cover member fits onto the base member over the v-groove and, together with the base member, defines end apertures which permit insertion of prepared fiber ends between the base member and the cover member into opposite ends of the elastomer alignment sleeve. The cover member includes two barbed studs which are pressed into respective apertures of the cover member to clamp protective material surrounding the fiber ends, and a screw-driven plunger which is driven against the elastomer alignment sleeve to urge the alignment sleeve into the v-groove, thereby compressing the alignment sleeve onto the abutting fiber ends to align and clamp the fiber ends.
Copending U.S. patent application Ser. No. 447,453, filed Dec. 7, 1989, in the names of H. H. Lukas et al has been allowed (U.S. Pat. No. 4,997,255) describes a mechanical splice in which three gripping members are resiliently biased against a base member at adjacent gripping positions along a reference surface of the base member. The reference surface of the base member has a groove for receiving the ends of optical fibers to be spliced. The outer two gripping members are used to grip protective material which surrounds the optical fiber ends, and the central gripping member is used to grip bare ends of the optical fibers from which the protective material has been stripped.